[alfa] Re: Stereo upgrading (Spider)

[Sonny <maxid@xxxxxxxxxxxxxx>]

I have never installed a stereo in a Spider, but I have done so in several
sedans and was at one point so much into car stereo that I even sat for and
passed the MECP certified car audio installer's test. My interest has come
down over the years, but here are my $0.02:

Decide what you want first. Do you want an audiophile system or simpy be sure
that you can overpower wind noise? An important part of an audiophile system
is staging and imaging. This means that the performers sound like they are in
front of you, on a stage, and you should be able to place each instrument
correctly on a left-right axis. This requires that the main speakers (i.e.
everything but the subwoofer(s)) are placed in front of you. If you put 6"x9"
two-way speakers behind you, you are never going to get any staging. I believe
your car is a late Spider and that it has speaker locations in the doors.
Mid-80's Spiders have speaker locations in the footwell kickpanels. Neither
location is optimal, but a decent starting point. Because unless you make
modifications to your car, you won't get an audiophile system, and anyway, an
audiophile system is somewhat of an oxymoron in a car that is driven with the
top down most of the time. As to making modifications, the saying goes, cut
your car, and you will live to regret it.

What I would do is probably to keep the Alpine unit you already have. You
don't say what media you are using, but you shouldn't expect that a newer unit
is better, only that it will play newer media. If you are like me who prefers
to listen to the rich offering of non-commercial NPR/college radio etc. in the
Baltimore-DC area, then all that matters is that it has a good tuner. The
older radio is less likely to give away to thieves that you have a nice amp
and speakers. Combine your radio with a _high quality_ line output converter
from Soundgate or similar, not a $20 unit from a big box store. Some amps also
accept high-level (speaker) inputs, but the step-down circuitry is sometimes
not as good as that of a high quality line output converter. Use a 4-channel
amp of 4x50 or 4x75 watts. Because you are going to use an external amp in a
convertible anyway the head unit's output power doesn't matter. Also, be aware
that whatever watts are advertised as the output of the head unit is highly
inflated. There is a reason that an external amp is 4 times as big as the
whole head unit itself. The front channels of your external amp drive the
front speakers. The other two channels, in bridged mode, drive a single 10" or
two 8" on some kind of baffle surreptitiously mounted behind the seats. Use
the amp's built-in crossover at around 90 Hz. If you use the correct front
speakers, it might actually sound very good even without mounting the tweeters
separate from existing cutouts in the doors. MB Quart and other brands have
coaxial speakers with titanium tweeters. Titanium tweeters are very bright.
The problem with mounting your woofers in the doors and the tweeters on the
dash is that you will get a dissociation of the sound as well as phase
cancellation.

I believe the Spider door cutouts are for 5.25 inch speakers. If they are
larger than that, theh they are 6.5 inch. Be aware that there are two 6.5 inch
sizes. The traditional one, which is actually 6.2 inches or 158 mm and the
newer one, which is 6.5 inches or 165 mm. Many car stereo professionals don't
have this detail straight.

Because of the twisted acoustics of the Spider with its top down, you might
also want an equalizer.

You might find some books to read on amazon.com. I used to go on carsound.com,
where they also used to offer a book and had the best online discussions.

Cheers,
Sonny
'91 164S
Balto.
--
to be removed from alfa, see /bin/digest-subs.cgi
or email "unsubscribe alfa" to majordomo@domain.elided